【摘要】 <正> 重复DNA顺序是真核生物基因组的特征,很多重复DNA顺序已从小麦、拟南芥菜、燕麦、水稻、玉米等植物的基因组中克隆出来,还发现有一些重复DNA顺序具有基因组特异性,用它们作探针可以分析同属或同科物种的起源和亲缘关系,并建立系统进化树。小卫星DNA或微小卫星DNA所产生的指纹图谱可作为一种遗传学标志来研究系统进化、染色体的精细结构和物种的鉴定。一些中度重复DNA序列还可以作为组织培养株系和细胞杂交筛选的分子标志。稻属已发现并定名的有22个种,根据杂交亲和性、细胞遗传学和生理生化等将它分为6个二倍体组型(AA、BB、CC、DD、EE和FF)和2个四倍体组型(BBCC和CCDD)。现多把禾本科分作5个亚科:竹亚科、稻亚科、早熟禾亚科、画眉草亚科和更多还原

【Abstract】 Some repetitive sequences have been cloned from rice genome by DNA renaturation kinetics . Using them as probes, Southern blotting analyses in 30 species of Oryza and Poaceae were carried out. The authors’ results indicated that hybridization band patterns correlated with relationship of plants. The use of these repetitive sequences as probes in phytogenetic classification is considered. The fragment of pRRD9 also showed polymorphisms among some ecological types of wild rice ( 0. rufipogon) , suggesting that it could be used as a probe in the study of rice evolution.更多还原